Question

Find the least number of square tiles required to pave the ceiling of a room 15 m 17 cm long and 9 m 2 cm broad.

Answer 1

Length of the room $=15m17cm=15\times 100+17=1517$ cm.

Breadth of the room $=9m2cm=902$ cm.

The HCF of the 1517 and 902 will be the size of square tiles.

HCF 1517 and 902 = 41 cm.

Area of the room $=length\times breadth=1517\times 902c{m}^2$.

Area of tiles $=41\times 41c{m}^2$

So, no. of tiles required $=\frac{1517\times 902}{41\times 41}=814$ tiles.